Electrical connector, in particular for a cutaneous device

ABSTRACT

An electrical connector, in particular for a medical device that is intended to be secured to the skin of a user, is disclosed. The connector includes a base for solidly connecting to the device and a plug for solidly connecting to an electric conductor. The plug includes a connection means and the base includes a plurality of connection means, each being adapted to engage with the connection means of the plug in order to establish a connection between the base and the plug.

The invention relates to the technical field of devices intended to befixed on the skin of a user.

It in particular involves medical devices, such as cutaneous electrodesfor measuring physiological parameters or impulse generators forelectrostimulation.

These devices are generally compact enough to be placed directly on auser's skin. They are designed also to be relatively thin and flexible.

These devices generally comprise an electrical connector making itpossible to connect the device to an electrical wire.

The electrical connector is made up of two parts:

a plug, i.e., the part of the connector situated at the end of theelectrical wire,

a base, i.e., the part of the connector secured to the device.

One commonly used electrical connector is of the “pushbutton” type.Generally, the plug comprises a cavity (female plug) and the basecomprises a protuberance (male base) intended to be inserted into thecavity.

Electrical connectors of the pushbutton type have drawbacks, inparticular when the user fastens the device on his skin beforeperforming the connection.

Indeed, pressure (i.e., a force perpendicular to the plane of thedevice) must be exerted to perform the connection, which may be painfulfor the user.

Furthermore, the user must position the cavity of the plug exactlyopposite the protuberance of the base before exerting the pressure.Thus, a visual inspection is necessary to make the connection quickly.As a result, making the connection may become an extremely long andtedious operation if this visual inspection is not possible. This forexample occurs when the user has fixed the device on his back or behindone of his legs.

Thus, with an electrical connector of the pushbutton type, it isgenerally preferable to fix the device on the skin after havingperformed the electrical connection, which is less practical for theuser.

Other types of connection have been proposed in the prior art.

In particular, electrical connectors comprising magnetic parts aredescribed in document U.S. Pat. No. 4,112,941.

This document specifically relates to the field of cutaneous electrodes,with a plug comprising a cavity (female plug) and a base comprising aprotuberance (male base). With the electrical connector described inthis document, it is no longer necessary to exert pressure to performthe connection, since the magnetic force between the plug and the basesuffices to insert the protuberance of the base into the cavity of theplug.

This therefore resolves one of the problems encountered with connectorsof the pushbutton type, since it is no longer necessary to exertpressure to make the connection.

However, a visual inspection is still necessary to perform theconnection quickly. Indeed, the user must at least pre-position thecavity of the plug near the protuberance of the base, before themagnetic forces begin to act and assemble the two parts of theconnector.

The invention aims to offset these drawbacks by proposing an electricalconnector, in particular for a medical device intended to be fixed onthe skin of a user, comprising a base secured to the device and a plugintended to be secured to an electrical conductor, which makes itpossible to perform a quick connection of the base and the plug withoutvisual inspection, and preferably without exerting pressure.

According to the invention, the plug comprises a connection means andthe base comprises a plurality of connection means, each of them beingsuitable for cooperating with the connecting means of the plug to ensurethe connection between the base and the plug.

Thus, the base includes a high density of potential connection zoneswith the plug, which makes it possible to perform a quick connectionbetween the base and the plug, with no visual inspection.

Preferably, the center-to-center distance between two adjacentconnecting means of the base is comprised between 1.5 and 10 times thesection of these connecting means.

Furthermore, the connecting means of the base are preferably distributeduniformly over the surface of the base.

The electrical connector according to the invention preferably includesmagnetic means on both the plug and the base.

The presence of these magnetic means prevents the user from having toexert pressure to make the connection between the plug and the base.

They therefore contribute to facilitating the connection between theplug and the base, with no visual inspection.

In a first embodiment, the base includes a plurality of holes and theplug includes a protuberance.

In this first embodiment of the connector, the base is made up of astack of at least two layers, one of them performing at least amechanical support function and said at least two layers also performingan electrical function and optionally a magnetic function, the holes ofthe base traversing at least the layer acting as mechanical support, andthe plug comprising a base and a protuberance performing an electricalfunction and optionally a magnetic function.

In a first form of the embodiment, the stack making up the basecomprises a layer performing a mechanical support function and a layerperforming an electrical function and optionally a magnetic function,the holes traversing the stack.

Furthermore, the electrical function and optionally magnetic function ofthe plug is performed by the base.

In a second form of the first embodiment of the connector, the stackmaking up the base comprises a layer performing an electrical functionand a layer performing a mechanical function, the layer performing anelectrical function also being able to perform a magnetic function, theholes only traversing the layer performing a mechanical function, theelectrical function and optionally magnetic function of the plug beingperformed by the protuberance.

In a third form of the first embodiment of the connector, the stackmaking up the base successively comprises a layer performing an electricfunction, a layer performing a mechanical function and optionally alayer performing a magnetic function, the holes traversing the layerperforming a magnetic function and, when it is present, the layerperforming a magnetic function, any magnetic function of the plug beingperformed by the base and the electrical function of the plug beingperformed by the protuberance.

In a first particular configuration, the potential magnetic function isperformed by the layer performing a magnetic function.

In a second particular configuration, a layer having an aestheticfunction is provided on the layer performing a mechanical function or onthe potential layer performing a magnetic function.

In a first alternative embodiment, the plug comprises an annular partprotruding on the base and extending around the protuberance, the basecomprising, around each hole, an annular opening to receive theprotruding annular part of the plug.

In a second alternative embodiment, the plug includes a protuberancehaving a flared shape becoming narrower as it moves away from the base,the holes of the base including a corresponding shape to receive thisprotuberance.

In a third alternative embodiment, the protuberance of the plugcomprises two parts performing an electrical function and optionally amagnetic function, separated by an insulator.

In a fourth alternative embodiment, the protuberance of the plug has aflared shape becoming wider as it moves away from the base, the holes ofthe base having a corresponding shape to receive this protuberance.

In a fifth alternative, the layer of the base that is not traversed bythe holes is a discontinuous layer, in particular assuming the form of agrid or independent parts that are not electrically connected.

The fifth alternative embodiment is applicable to the second and thirdforms of the first embodiment of the connector.

The sixth alternative embodiment is applicable to the first and thirdforms of the first embodiment.

In this sixth alternative, a layer traversed by the holes is adiscontinuous layer.

In a seventh alternative embodiment, the protuberance of the plugperforms an elastic function to establish better electrical contact.

In an eighth alternative applicable to the second and third forms, thelayer performing an electrical function is made up of two separate partsthat are not electrically connected, the protuberance or the base of theplug making it possible to electrically connect these two parts when theplug is connected to the base.

In a second embodiment, the base includes a plurality of protuberancesand the plug includes a cavity.

In this case, the base comprises at least one layer performing amechanical support function and the plurality of protuberances is madedirectly on the mechanical support layer or on an intermediate layer,the protuberances, the layer performing a mechanical support function orthe intermediate layer performing an electrical function and optionallya magnetic function, and the plug comprises a cylindrical part definingthe cavity that is closed by a base, the electrical function of the plugbeing performed by the cylindrical part or the base and the potentialmagnetic function of the plug being performed by the cylindrical part orthe base.

In a first form of this second embodiment of the connector, the basecomprises, on the layer performing a mechanical support function, apotential intermediate layer, the electrical function and the potentialmagnetic function being performed by the layer performing a mechanicalsupport function or the potential intermediate layer, the protuberancesbeing made on the layer performing a mechanical support function or onthe intermediate layer, the electrical function and the potentialmagnetic function of the plug being performed by the cylindrical part.

In a second form of the embodiment, the base comprises, on the layerperforming a mechanical support function, protuberances made directly onthis mechanical support layer, these protuberances performing anelectrical function and optionally a magnetic function, the electricalfunction and the potential magnetic function of the plug being performedby the base.

In a third form of the second embodiment of the connector, the basecomprises, on the layer performing a mechanical support function, anintermediate layer performing an electrical function, the protuberancesbeing made on this intermediate layer and optionally performing amagnetic function, the cylindrical part of the plug performing anelectrical function and its base optionally performing a magneticfunction.

In one alternative of this third form, it is the protuberances thatperform an electrical function and the intermediate layer thatoptionally performs a magnetic function.

The connector according to the invention may include a plurality ofplugs, the number of which is strictly smaller than that of theconnecting means of the base.

The invention also relates to a medical device intended to be fixed onthe skin of a user, of the patch type.

In this case, the connecting means of the base are advantageouslydistributed so as to occupy more than 1% of the total surface area ofthe device, and in particular more than 5% of this surface area.

The invention will be better understood, and other aims, advantages andfeatures thereof will appear more clearly, upon reading the followingdescription done in reference to the appended drawings, in which:

FIG. 1 (1A-1B) comprises a top view (FIG. 1A) and a sectional view (FIG.1B) of a female base corresponding to a first embodiment of theconnector,

FIG. 2 (2A-2F) shows, in top view (FIGS. 2A, 2C, 2E) and sectional view(FIGS. 2B, 2D, 2F), three examples of male plugs adapted to the baseillustrated in FIG. 1, the base according to FIG. 1 being illustrated indotted lines in FIGS. 2B to 2F,

FIG. 3 (3A-3B) shows a top view (FIG. 3A) and a sectional view (FIG. 3B)of a female base corresponding to a second form of the embodiment of theconnector according to the invention,

FIG. 4 (4A-4F) shows top views (FIGS. 4A, 4C, 4E) and sectional views(FIG. 4B, 4D, 4F) of examples of male plugs adapted to the baseillustrated in FIG. 3, the space being partially illustrated in dottedlines in FIGS. 4B, 4D and 4F,

FIG. 5 (5A-5B) comprises a top view (FIG. 5A) and a sectional view (FIG.5B) of a female base corresponding to a third form of the embodiment ofthe connector, and adapted to the male plug illustrated in FIG. 6,

FIG. 6 (6A-6B) comprises a top view (FIG. 6A) and a sectional view (FIG.6B) of the example of the male plug adapted to the base illustrated inFIG. 5,

FIG. 7 (7A-7B) comprises a top view (FIG. 7A) and a sectional view (FIG.7B) of a first alternative embodiment of a male plug adapted to thebases illustrated in FIGS. 1, 3 and 5,

FIG. 8 (8A-8B) comprises a top view (FIG. 8A) and a sectional view (FIG.8B) of a female base of the type illustrated in FIG. 1 and adapted tothe alternative of the plug illustrated in FIG. 7, the plug illustratedin FIG. 7 being shown connected to the base in FIG. 8B,

FIG. 9 is a sectional view of a second alternative of a male plug,intended to be connected to a female base of the type illustrated inFIGS. 1, 3 and 5,

FIG. 10 is a sectional view of a female base of the type illustrated inFIG. 1, adapted to the plug illustrated in FIG. 9, this plug also beingillustrated connected to this base,

FIG. 11 is a sectional view illustrating a third alternative embodimentof the male plug adapted to one of the female bases illustrated in oneof FIG. 3 or 5,

FIG. 12 (12A-12B) comprises a top view (FIG. 12A) and a sectional view(FIG. 12B) of a base of the type illustrated in FIG. 3 and adapted tothe plug illustrated in FIG. 11,

FIG. 13 is a sectional view showing a fourth alternative embodiment of amale plug adapted to the female bases described in reference to FIGS. 1,3 and 5,

FIG. 14 is a top view of a base of the type illustrated in FIG. 1 andadapted to the plug illustrated in FIG. 3,

FIG. 15 (15A-15E) shows top views of examples of the lower layer of afemale base, as illustrated in FIGS. 3 and 5, corresponding to a fifthalternative embodiment,

FIG. 16 is a sectional view of a base of the type illustrated in FIG.15D according to the fifth alternative embodiment, a male plug of thetype illustrated in FIG. 6 being connected on this base,

FIG. 17 (17A-17B) comprises a top view (FIG. 17A) and a sectional view(FIG. 17B) showing a sixth alternative embodiment of the baseillustrated in FIG. 5,

FIG. 18 is a sectional view of a cutaneous electrode comprising a baseaccording to FIG. 5,

FIG. 19 (19A-19B) comprises a sectional view (FIG. 19A) of a patchgenerating impulses and including a base according to FIG. 15D and a topview (FIG. 19B) of the electrical diagram of the patch illustrated inFIG. 19A,

FIG. 20 (20A-20B) comprises FIG. 20A showing the devices illustrated inFIGS. 18 and 19 in place on a user's body, the electrode according toFIG. 18 and the patch according to FIG. 19 on the body of a user andFIG. 20B illustrating the elastic band connecting these two devices,

FIG. 21 (21A-21B) illustrates a first form of the embodiment of a malebase shown in top view (FIG. 21A) and in sectional view (FIG. 21B),

FIG. 22 (22A-22B) shows a top view (22A) and a sectional view (22B) ofthe female plug adapted to the base illustrated in FIG. 21,

FIG. 23 (23A-23B) illustrates a second form of the embodiment of a malebase, FIG. 23A illustrating this base seen from above and FIG. 23Billustrating it in sectional view,

FIG. 24 (24A-24B) shows a top view (24A) and a sectional view (FIG. 24B)of the female plug adapted to the base illustrated in FIG. 23,

FIG. 25 (25A-25B) illustrates a third form of the embodiment of a malebase, seen from above (FIG. 25A) and in sectional view (FIG. 25B),

FIG. 26 (26A-26B) shows a top view (FIG. 26A) and a sectional view (FIG.26B) of a female plug adapted to the male base illustrated in FIG. 25.

The elements shared by the different figures will be designated usingthe same references.

FIGS. 1 to 6 illustrate several forms of an embodiment of a connectoraccording to the invention including a female base with a plurality ofholes and a male plug with a protuberance.

Thus, FIGS. 1 and 2 illustrate a first form of an embodiment of such aconnector in which the base comprises:

-   -   an upper layer having an electrical and magnetic function,    -   a lower layer having a mechanical function,    -   a plurality of holes traversing the upper layer and the lower        layer.

FIGS. 3 and 4 illustrate a second form of such a connector in which thebase comprises:

-   -   an upper layer having a mechanical function,    -   a lower layer having an electrical and magnetic function,    -   a plurality of holes traversing only the upper layer.

FIGS. 5 and 6 illustrate a third form of such a connector in which thebase comprises:

-   -   an upper layer having a magnetic function,    -   an intermediate layer having a mechanical function,    -   a lower layer having an electrical function,    -   a plurality of holes traversing only the upper layer and the        intermediate layer.

A first configuration of this third form of the embodiment (notillustrated in the figures) consists of eliminating the upper layer, thepotential magnetic function being performed by the intermediate layer.

A second configuration of this third form (not illustrated in thefigures) consists of adding a layer, in particular having an aestheticfunction, above the layer having a magnetic function. Thus, the basethen comprises four layers:

-   -   a layer having an aesthetic function,    -   a layer having a magnetic function,    -   a layer having a mechanical function,    -   a layer having an electrical function,    -   a plurality of holes traversing only the layer having an        aesthetic function, the layer having a magnetic function and the        layer having a mechanical function.

When the layer having a mechanical function also has a magneticfunction, the layer having an aesthetic function is provided directly onthis layer.

In each of these three forms:

-   -   The layer of the base having an electrical function is intended        to establish electrical contact with the part of the plug having        an electrical function.    -   The layer of the base having an electrical function is made from        an electrically conductive material and for example a metal,        such as copper, silver, gold, aluminum, iron or steel; or a        polymer filled with carbon black or metal elements; or a        conductive textile material.    -   Advantageously, it is a thin, or even flexible, layer.    -   If the layer is made from a metal or a metal alloy, the        thickness of the layer is advantageously comprised between 0.001        mm and 1 mm, and preferably between 0.01 mm and 0.2 mm. If the        layer is made from a polymer filled with carbon black or metal        elements, or a conductive textile material, the thickness of the        layer is advantageously comprised between 0.1 mm and 5 mm, and        preferably between 0.5 mm and 2 mm.    -   The layer of the base having a magnetic function and the part of        the plug having a magnetic function are intended to exert an        attractive magnetic force on one another.    -   The layer of the base having a magnetic function is made from a        ferromagnetic material, for example iron, magnetic steel,        cobalt, nickel, or polymer filled with ferromagnetic elements or        a magnetized material, for example aluminum-nickel-cobalt,        samarium-cobalt, neodyme-iron-boron, or a polymer filled with        magnetized elements.    -   Advantageously, it is a thin, or even flexible, layer.    -   If the layer of the base is made from a metal or an alloy of        metals, the thickness of the layer is advantageously comprised        between 0.001 mm and 1 mm, preferably between 0.1 mm and 0.2 mm.        If the layer is made from a polymer filled with their magnetic        or magnetized elements, the thickness of the layer is        advantageously comprised between 0.1 mm and 5 mm, and preferably        between 0.5 mm and 2 mm.    -   The layer of the base having the mechanical function is        traversed by the holes. Any one of these holes is intended to        receive the protuberance of the plug and to thereby prevent        accidental disconnection via lateral forces, i.e., forces in the        plane of the base.    -   The layer of the base having a mechanical function is thick        enough to ensure the lateral maintenance of the protuberance and        therefore of the plug.    -   Advantageously, the thickness of the layer is comprised between        0.1 mm and 5 mm, and preferably between 0.5 mm and 2 mm.    -   Advantageously, the layer is formed from a very flexible        material (for example, a polymer or a textile material), in        order to remain flexible despite its relatively significant        thickness.    -   The surface density of holes on the base is high enough to allow        a fast connection without visual inspection.    -   This is facilitated by the action of the magnetic forces.        However, this density of holes makes it possible to obtain a        connection with no visual inspection, even in the absence of        parts performing a magnetic function inside the connector.    -   However, in the presence of parts performing a magnetic        function, one can see that a small lateral movement of the plug        near the surface of the base suffices for the magnetic forces to        become active and assemble the two parts of the connector,        causing the insertion of the protuberance of the plug in one of        the holes of the base.    -   In other words, the high surface density of potential connection        zones (the holes of the base), combined with the action of the        magnetic forces, makes a connection with no visual inspection        even faster and easier.    -   Advantageously, the diameter of the holes (considering        cylindrical holes) is comprised between 0.1 mm and 10 mm, and        preferably between 0.5 mm and 5 mm. Advantageously, the        center-to-center distance between two adjacent holes with an        identical diameter is comprised between 1.5 times the diameter        of a hole and 10 times the diameter, preferably between 1.5        times the diameter and 5 times the diameter. The holes do not        necessarily have a circular shape, but may for example be        oblong.    -   Advantageously, the holes of the base are distributed uniformly        over the surface of the base.    -   If the base is intended for a device worn in the form of a        patch, the sum of the surface areas occupied by the holes        advantageously corresponds to more than 1% of the total surface        area of the patch, and preferably more than 5% of the total        surface area of the patch.

Furthermore, in all of these forms, the plug comprises:

-   -   a part serving as a protuberance,    -   a part having an electrical function (i.e., a part made from an        electrically conductive material, for example a metal, such as        copper, silver, gold, aluminum, iron or steel; or polymer filled        with carbon black or metallic elements),    -   a part having a magnetic function (i.e., a part made from a        ferromagnetic material, for example iron, magnetic steel,        cobalt, nickel; or a part made from a magnetized material, for        example ferrite, aluminum-nickel-cobalt, samarium-cobalt,        neodyme-iron-boron).

In reference first to FIGS. 1 and 2, FIGS. 1A (top view) and 1B(sectional view along line I-I of FIG. 1A) show the base 20 of theelectrical connector.

The base 20 comprises an upper layer 21 (with thickness e_(E)) having anelectrical and magnetic function, and a lower layer 22 (with thicknessE_(E)) having a mechanical function.

The base 20 comprises a plurality of cylindrical holes 23 (with diameterD_(E)) traversing the upper layer 21 and the lower layer 22.

The holes 23 here form of periodic network (with period P_(E)). Theupper layer 21 is for example a sheet of magnetic stainless steel; itmay be a flexible sheet.

The lower layer 22 is for example a sheet of polymer or textilematerial; it may be a flexible layer.

Advantageously, the thickness e_(E) of the upper layer 21 is comprisedbetween 0.001 mm and 0.5 mm, and preferably, between 0.01 mm and 0.2 mm.For example, the upper layer 21 is a flexible sheet of AISI 420 magneticstainless steel, with thickness e_(E)=0.075 mm.

Advantageously, the thickness E_(E) of the lower layer 22 is comprisedbetween 0.1 mm and 5 mm, preferably between 0.5 mm and 2 mm. Forexample, the lower layer 22 is a flexible layer, made from siliconeelastomer or polyurethane foam, with thickness E_(E)=1 mm.

The diameter D_(E) of the holes 23 is advantageously comprised between0.1 mm and 10 mm, and preferably between 0.5 mm and 5 mm. The periodP_(E) of the network of holes 23 is advantageously comprised between1.5×D_(E) and 10×D_(E), and preferably between 1.5×D_(E) and 5×D_(E).

FIGS. 2A (top view) and 2B (sectional view along line II-II in FIG. 2A)show a first example plug 100 of the electrical connector.

This plug is secured to an electrical conductor, for example a wire or apower cable (not shown in the figures).

Examples of such electrical conductors will be described in reference toFIG. 20.

The plug 100 comprises a cylindrical part 101, with diameter D_(F) andthickness E_(F), having an electrical and magnetic function, and acylindrical part 102, with diameter d_(F) and thickness e_(F), forming aprotuberance.

The two cylindrical parts 101 and 102 are centered around the same axis.

The part 101 is for example a part made from aluminum-nickel-cobalt, orsamarium-cobalt, or neodyme-iron-boron, which are magnetizedelectrically conductive materials.

The protuberance 102 is for example a metal part.

FIGS. 2C (top view) and 2D (sectional view along line II-II in FIG. 2C)show a second example plug 110.

In place of the part 101, the plug 110 comprises an annular part 111having a magnetic function and a cylindrical part 112 having anelectrical function, placed in the central recess of the part 111. Thethree parts 111, 112 and 102 are centered around a same axis.

The part 111 is for example a part made from ferrite, oraluminum-nickel-cobalt, or samarium-cobalt, or neodyme-iron-boron, whichare magnetized materials. The part 112 is for example a metal part.

FIGS. 2E (top view) and 2F (sectional view along line II-II in FIG. 2E)show a plug 120 that is an alternative of the plug 110.

In the plug 120, the annular part 121 having a magnetic function isslightly withdrawn (advantageously by several millimeters) from thecylindrical part 122 having an electrical function.

The outer diameter D_(F) of the part 101, 111 or 121 is greater than theD_(E). The diameter d_(F) of the protuberance 102 is smaller than D_(E).

The thickness e_(F) of the protuberance 102 is advantageously slightlysmaller than the sum e_(E)+E_(E). For example, e_(E)=0.075 mm, E_(E)=1mm, D_(E)=1 mm, P_(E)=4 mm, D_(F)=6 mm, E_(F)=1 mm, d_(F)=0.8 mm, ande_(F)=0.8 mm.

FIG. 2B also shows the plug 101 once connected to the base 20, which ispartially shown in dotted lines.

One of the holes 23 accommodates the protuberance 102, which preventsaccidental disconnection due to lateral forces, i.e., forces in theplane of the base 20. The upper layer 21 establishes electrical contactwith the part 101. The upper layer 21 and the part 101 exert anattractive magnetic force on one another.

The intensity of the magnetic force between the upper layer 21 and thepart 101 in particular depends on the nature and dimensions of the upperlayer 21 and the part 101.

According to the physical laws of magnetism, the intensity of themagnetic force also depends on the architecture of the plug 100containing the part 101. For example, by placing the magnetized part 101in a cup-shaped ferromagnetic part (not shown in FIG. 2B), it ispossible to concentrate the magnetic flow on the free edges of themagnetized part 101, which increases the magnetic force. Advantageously,the intensity of the magnetic force is comprised between 100 g and 1000g. Such an intensity range is achievable with the materials anddimensions previously mentioned, in particular if the part 101 is madefrom neodyme-iron-boron.

FIG. 2D also shows the plug 110 once connected to the base 20.

The upper layer 21 establishes electrical contact with the part 112. Theupper layer 21 and the part 111 exert an attractive magnetic force onone another.

FIG. 2F also shows the plug 120 once connected to the base 20.

The upper layer 21 establishes electrical contact with the part 122. Theupper layer 21 and the part 121 exert an attractive magnetic force onone another.

Given that the part 121 is slightly withdrawn from the part 122, thepressure exerted by the part 122 on the upper layer 21 is increased, andtherefore the electrical contact between the upper layer 21 and the part122 is improved. In other words, the electrical resistance of thecontact is decreased.

In reference now to FIGS. 3 and 4, FIGS. 3A (top view) and 3B (sectionalview along line III-III in FIG. 3A) show the base 50 of the electricalconnector.

The base 50 comprises an upper layer 51 having a mechanical function,and a lower layer 52 having an electrical and magnetic function.

The base 50 comprises a plurality of cylindrical holes 53 traversingonly the upper layer 51. The holes 53 here form a periodic network.

The upper layer 51 is for example a flexible layer made from polymer ortextile material or made from silicone elastomer or polyurethane foam,the thickness of which is 1 mm.

The lower layer 52 is for example a flexible sheet of magnetic stainlesssteel, for example AISI 420 magnetic stainless steel, the thickness ofwhich is 0.075 mm.

Relative to the first form illustrated in FIG. 1, one advantage of thesecond form lies in the fact that the layer of the base having anelectrical function is not the upper layer of the base. This provides again in terms of the safety and reliability of the device.

Indeed, the user cannot easily access the parts intended to be poweredon (such as the layer having an electrical function), which limits theelectrical risks (for the user) and the risks of malfunction (for thedevice).

FIGS. 4A (top view) and 4B (sectional view along line IV-IV in FIG. 4A)show a first example of the plug 400 of the electrical connector.

The plug 400 comprises a cylindrical part 401. The plug 400 comprisesanother cylindrical part 402 forming a protuberance and performing anelectrical and magnetic function.

The two cylindrical parts 401 and 402 are centered around a same axis.

The part 401 is for example a metal part.

The protuberance 402 is for example a part made fromaluminum-nickel-cobalt, or samarium-cobalt, or neodyme-iron-boron, whichare magnetized electrically conductive materials.

FIGS. 4C (top view) and 4D (sectional view along line IV-IV in FIG. 4C)show a second example of a plug 410.

In place of the protuberance 402, the plug 410 comprises a protuberance413 formed from an annular part 411 having a magnetic function and acentral cylindrical part 412 having an electrical function.

The three parts 401, 411 and 412 are centered around a same axis.

The part 411 is a part for example made from ferrite, oraluminum-nickel-cobalt, or samarium-cobalt, or neodyme-iron-boron, whichare magnetized materials. The part 412 is for example a part made frommetal.

FIGS. 4E (top view) and 4F (sectional view along line IV-IV in FIG. 4E)show a plug 420 that is an alternative of the plug 410.

In the protuberance 423 of the plug 420, the annular part 421 having amagnetic function is slightly withdrawn (advantageously by severalmillimeters) from the central cylindrical part 422 having an electricalfunction.

FIG. 4B also shows the plug 400 once connected to the base 50.

One of the holes 53 receives the protuberance 402, which preventsaccidental disconnection due to lateral forces, i.e., forces in theplane of the base 50.

The lower layer 52 establishes electrical contact with the protuberance402.

The lower layer 52 and the protuberance 402 exert an attractive magneticforce on one another.

Advantageously, the height of the protuberance 402 is equal to orslightly greater than the thickness of the layer 51.

However, the height of the protuberance 402 can be slightly smaller thanthe thickness of the layer 51. In this case, the compressibility of thelayer 51 or the flexibility of the layer 52 make it possible to adapt tothe situation to produce electrical contact.

In order to improve the electrical contact between the lower layer 52and the protuberance 402, and to avoid dirtying of these parts that maylead to poor electrical contact, the lower layer 52 and the protuberance402 can have shapes different from those shown in FIG. 4B.

In particular, the end of the protuberance 402, i.e., the part cominginto contact with the lower layer 52, is not necessarily planar, but mayhave a rounded or pointed shape. In this case, the exposed zones of thelower layer 52, i.e., the zones on which the holes 53 emerge, are notnecessarily planar, but may be in the form of a cavity making itpossible to receive the rounded or pointed end of the protuberance 402.

Another method for improving the electrical contact between theprotuberance 402 and the base 50 consists of metallizing the inner wallsof the holes 53. In this case, the protuberance 402 can establishelectrical contact via its end or via its flanks.

FIG. 4D also shows the plug 410 once connected to the base 50.

The lower layer 52 establishes electrical contact with the part 412.

The lower layer 52 and the part 411 exert an attractive magnetic forceon one another.

FIG. 4F also shows the plug 420 once connected to the base 50.

The lower layer 52 establishes electrical contact with the part 422.

The lower layer 52 and the part 421 exert an attractive magnetic forceon one another.

Given that the part 421 is slightly withdrawn from the part 422, thepressure exerted by the part 422 on the lower layer 52 is increased, andtherefore the electrical contact between the lower layer 52 and the part422 is improved. In other words, the electrical resistance of thecontact is decreased.

In reference to FIGS. 5 and 6, FIGS. 5A (top view) and 5B (sectionalview along line V-V in FIG. 5A) show the base 80 of the electricalconnector.

The base 80 comprises an upper layer 81 having a magnetic function, anintermediate layer 84 having a mechanical function, and a lower layer 82having an electrical function.

The base 80 comprises a plurality of cylindrical holes 83 traversingonly the upper layer 81 and the intermediate layer 84. The holes 83 hereform of periodic network.

The upper layer 81 is for example a flexible sheet of magnetic stainlesssteel, in particular an AISI 420 magnetic stainless steel, with athickness of 0.075 mm.

The intermediate layer 84 is for example a flexible layer made frompolymer or textile material, or a silicone elastomer or polyurethanefoam, the thickness of which is 1 mm.

The lower layer 82 is for example a metal-polymer bilayer (the metallayer being above the polymer layer) or a copper-polyamide bilayer (witha copper layer having a thickness of 0.035 mm and a polyamide layer witha thickness of 0.045 mm).

Relative to the first form illustrated in FIG. 1, one advantage of thisthird form lies in the fact that the layer of the base having anelectrical function is not the upper layer of the base, which provides again in terms of the safety and reliability of the device.

FIGS. 6A (top view) and 6B (sectional view along line VI-VI in FIG. 6A)show the plug 700 of the electrical connector.

The plug 700 comprises an annular part 701 forming its base, having amagnetic function, and a central cylindrical part 702 forming aprotuberance 702 a, protruding relative to the annular part 701, andhaving an electrical function.

The two parts 701 and 702 are centered around a same axis.

The part 701 is for example a ferrite part, or aluminum-nickel-cobalt orsamarium-cobalt or neodyme-iron-boron, which are magnetized materials.

The protuberance 702 is for example a metal part.

FIG. 5B also shows the plug 700 once connected to the base 80.

One of the holes 83 accommodates the protuberance 702 a, which preventsan accidental disconnection due to lateral forces, i.e., forces in theplane of the base 80.

The lower layer 82 establishes electrical contact with the protuberance702. The upper layer 81 and the part 701 exert an attractive magneticforce on one another.

The height of the protuberance 702 a is equal to or slightly larger thanthe sum of the thicknesses of the layers 81 and 84.

In order to improve the electrical contact between the lower layer 82and the protuberance 702 a, and prevent dirtying of these parts that maylead to poor electrical contact, the lower layer 82 and the protuberance702 a may have shapes different from those shown in FIGS. 5 and 6.

In particular, the end of the protuberance 702 a, i.e., the part cominginto contact with the lower layer 82, is not necessarily planar, but mayhave a rounded or pointed shape.

In this case, the exposed zones of the lower layer 82, i.e., the zoneson which the holes 83 emerge, are not necessarily planar, but can be inthe form of a cavity making it possible to receive the rounded orpointed end of the protuberance 702.

Another method for improving the electrical contact between theprotuberance 702 and the base 80 consists of analyzing the inner wallsof the holes 83. In this case, the protuberance 702 can establishelectrical contact via its end or via its flanks.

In all of the forms illustrated in FIGS. 1 to 6, the holes of the baseare cylindrical, and the plug has a symmetry of revolution around anaxis perpendicular to the plane of the base.

This is advantageous, since in this way, the electrical connectionbetween the plug and the base can be established for any orientation ofthe plug. Of course, the plane of the plug should be parallel to theplane of the base, which is in particular ensured by the magneticforces.

However, the invention is not limited to this form.

Furthermore, in all of the forms illustrated in FIGS. 1 to 6, the baseand the plug include a part performing a magnetic function.

However, even in the absence of parts performing a magnetic function,the connectors described in reference to these figures make it possibleto produce an electrical connection with no visual inspection.

FIGS. 7 to 17 show alternative embodiments of the connector illustratedin FIGS. 1 to 6.

Thus, FIGS. 7 and 8 illustrate a first alternative.

FIGS. 7A (top view) and 7B (sectional view along line VII-VII in FIG.7A) show the plug 1000 of the electrical connector.

Relative to the plug 100 illustrated in FIG. 2, the plug 1000additionally comprises an annular part 1001 forming a protuberance.

The three parts 101, 102 and 1001 are centered around a same axis.

The plug 1000 retains a symmetry of revolution around an axis.

FIGS. 8A (top view) and 8B (sectional view along line VIII-VIII in FIG.8A) show the base 1100 of the electrical connector, modified to adapt tothe plug illustrated in FIG. 7. Thus, relative to the base 20illustrated in FIG. 1, the base 1100 additionally comprises annularholes 1101.

Each hole 23 is surrounded by an annular hole 1101, the two holes beingcentered around a same axis. The assembly formed by a cylindrical hole23 and an annular hole 1101 therefore has a symmetry of revolutionaround the same central axis.

FIG. 8B shows the plug 1000 once connected to the base 1100.

One of the cylindrical holes 23 receives the protuberance 102, while thecorresponding annular hole 1101 receives the protuberance 1001.

Relative to the case described in FIG. 2B, the mechanical strength ofthe connection with respect to the lateral forces is improved, since anadditional protuberance (the protuberance 1001) is present.

Advantageously, the diameter of the protuberance 102 is such that theprotuberance 102 cannot be introduced into an annular hole 1101.

This first alternative is described in relation to FIGS. 1 and 2, but italso applies to the connector described in relation to FIGS. 3, 4 and 5,6.

FIGS. 9 and 10 illustrate a second alternative embodiment of theconnector.

FIG. 9 shows the plug 1300 of the electrical connector.

Unlike the protuberance 102 of the plug 100 illustrated in FIG. 2B, theprotuberance 1301 of the plug 1300 has a flared shape close to its base.In other words, the diameter of the protuberance decreases moving awayfrom the base 101 of the plug.

The plug 1300 retains a symmetry of revolution around an axis.

FIG. 10 shows the base 1302 of the electrical connector. Unlike theholes 23 of the base 20 illustrated in FIG. 1, the holes 1303 of thebase 1302 have a flared shape close to the layer 21 of the base. Inother words, the holes widen near the layer 21. Each hole 1303 retains asymmetry of revolution around an axis.

FIG. 10 also shows the plug 1300 once connected to the base 1302. Theflared shape of the protuberance 1301 and the holes 1303 facilitates theconnection, by guiding the insertion of the protuberance 1301 into ahole 1303.

This second alternative is described in relation to FIGS. 1 and 2, butit also applies to the connector described in relation to FIGS. 3, 4 and5, 6.

FIGS. 11 and 12 illustrate a third alternative embodiment of theconnector.

FIG. 11 illustrates the plug 1500 of the electrical connector.

Unlike the protuberance 402 of the plug 400 illustrated in FIG. 4B, theprotuberance 1504 of the plug 1500 makes it possible to transmit not asingle electrical signal, but two electrical signals.

Indeed, the protuberance of the plug 1500 is made up of a centralcylindrical part 1501 having an electrical and magnetic function, anannular part 1502 having an electrically insulating function, and anannular part 1503 having an electrical and magnetic function. The parts1501 and 1503, electrically insulated by the part 1502, can eachtransmit a different electrical signal.

The four parts 401, 1501, 1502 and 1503 are centered around a same axis.The plug 1500 thus retains a symmetry of revolution around a same axis.

FIGS. 12A (top view) and 12B (sectional view along line XII-XII in FIG.12A) show the base 1600 of the electrical connector, modified to adaptto the plug illustrated in FIG. 11.

Unlike the lower layer 52 of the base 50 illustrated in FIG. 3, thelower layer of the base 1600 makes it possible to transmit not a singleelectrical signal, but two electrical signals.

Indeed, the lower layer of the base 1600 is made up of a layer 1601playing an electrical and magnetic role, a layer 1602 having anelectrically insulating function, and a layer 1603 having an electricaland magnetic function. The layers 1601 and 1603, electrically insulatedby the layer 1602, can each transmit a different electrical signal.

FIG. 12B also shows the plug 1500, once connected to the base 1600.

The layer 1601 establishes electrical contact with the part 1501.Furthermore, the layer 1601 and the part 1501 exert an attractivemagnetic force on one another.

The layer 1603 establishes electrical contact with the part 1503.Furthermore, the layer 1603 and the part 1503 exert an attractivemagnetic force on one another.

This third alternative is described in relation to FIGS. 3 and 4, but italso applies to the connector described in reference to FIGS. 5 and 6.

FIGS. 13 and 14 illustrate a fourth alternative embodiment of theconnector according to the invention.

FIG. 13 shows the plug 1800 of the electrical connector.

Relative to the plug 100 illustrated in FIG. 2B, the plug 1800 has ashape widening as it moves away from the base. More particularly, theplug 1800 illustrated in FIG. 3 comprises a cylindrical part 1801fastened to the end of the protuberance 102, the diameter of thecylindrical part 1801 being larger than that of the cylindrical part102. The three parts 101, 102 and 1801 are centered around a same axis.The plug 1800 therefore retains a symmetry of revolution around a sameaxis.

FIG. 14 shows the base 1802 of the electrical connector, which is of thetype illustrated in FIG. 1. It shows that the upper 21 and lower 22layers of the base 1802 are modified to adapt to the plug illustrated inFIG. 13.

The holes 1803 traversing the upper layer 21 have a different shape fromthe holes 1804 traversing the lower layer 22. Thus, the holes 1803 areformed by a large cylinder and a small cylinder, while the holes 1804are simply cylindrical. The holes 1803 and 1804 are aligned, as shown inFIG. 14 (the dotted lines of this figure indicate the position of theholes 1804 relative to the holes 1803).

The diameter of the part 102 is smaller than the diameter of the smallcylinder of the holes 1803, and therefore smaller than the diameter ofthe large cylinder of the holes 1803. The diameter of the part 1801 islarger than the diameter of the small cylinder of the holes 1803, butsmaller than the diameter of the large cylinder of the holes 1803.

The protuberance of the plug 1800 is inserted in the base 1802, firstpassing through the large cylinder of the hole 1803, then through theunderlying hole 1804. After this insertion, the part 1801 is found inthe hole 1804, at the vertical of the large cylinder of the hole 1803.In this so-called “unlocked” position, the protuberance of the plug 1800prevents accidental disconnection due to lateral forces, but does notoppose any resistance to vertical forces.

From the “unlocked” position, the protuberance of the plug 1800 can bemoved laterally to the right such the part 1801 remains of the hole 1804but is found at the vertical of the small cylinder of the hole 1803. Inthis so-called “locked” position, the protuberance of the plug 1800prevents an accidental disconnection due to lateral forces, and moreoveropposes resistance to vertical forces. Indeed, the diameter of the part1801 is larger than the diameter of the small cylinder of the hole 1803.

The electrical connector shown in FIGS. 13 and 14 therefore makes itpossible to strengthen the resistance to an accidental disconnection, byplacing the plug in a “locked” position.

Other shapes of holes 1803 can be considered to provide a “locked” mode.For example, the holes 1803 can be formed by a large cylinder surroundedby a plurality of small cylinders.

FIGS. 15 and 16 illustrate a fifth alternative embodiment of a connectorincluding a base of the type illustrated in FIGS. 3 and 5, i.e.,including a lower layer 52 or 82 not traversed by holes.

FIG. 15A shows the lower curve 1401 of the base according to the fifthalternative, the sectional view of which along line XIV-XIV of FIG. 15Ais similar to that of the base 50 illustrated in FIG. 3B or FIG. 5B.Unlike the lower layer 52 of the base 50 illustrated in FIG. 3, thelower layer 1401 of this base is not a continuous layer, but a layer ingrid form: the flexibility of the lower layer is therefore improved.This grid is made up of horizontal strips 1401 a and vertical strips1401 b. The holes 53 emerge in solid zones of the grid 1401.

The lower layer of the base can assume other forms, like thoseillustrated in FIGS. 15B and 15C.

Thus, the lower layer 1402 includes as many vertical strips 1402 b asthe grid 1401 of FIG. 15A, but only two horizontal strips 1402 a.

The lower layer 1403 includes only a single horizontal strip 1403 a andas many vertical strips 1403 b as the grid 1401.

The interest of the layers 1402 and 1403 is to further increase themechanical flexibility of the lower layer of the base.

These embodiments are possible as long as the material forming the lowerlayer has a high enough electrical conductivity. Indeed, in this case,all of the horizontal strips of FIG. 15A are not necessarily needed toconduct electrical current.

FIG. 15D shows the lower curve 1912 of the base of the electricalconnector. Unlike the lower layer 82 of the base 80, illustrated in FIG.5, the lower layer 1912 of the base illustrated in FIG. 15D is not acontinuous layer, but a layer made up of two parts 1912A and 1912B thatare separate and not electrically connected.

FIG. 16 is a sectional view of the base along line XVI-XVI in FIG. 15D.It illustrates that the holes 83 of the base emerge over zonescomprising both a portion of the part 1912A and a portion of the part1912B. In the case of the example illustrated in FIG. 15D, the two parts1912A and 1912B form an interdigitated structure, but other forms andstructures can be considered.

FIG. 16 shows the plug 700 once connected to the base 1910. The twoparts 1912A and 1912B establish electrical contact with the protuberance702 a. Furthermore, the protuberance 702 a makes it possible to connectthe part 1912A electrically to the part 1912B.

Thus, the base 1910 performs both a connector and switch function. Thisis particularly advantageous, as will be explained in the continuationof the description.

Furthermore, the fact that the lower layer 1912 is not a continuouslayer may advantageously give the base 1910 greater flexibility.

In the example illustrated in FIG. 15D, the lower layer is made up oftwo separate parts that are not electrically connected.

It is possible to generalize this concept to the case of a higher numberof separate parts that are not electrically connected: this is forexample the case of the lower layer 1916, illustrated in FIG. 15E,intended for another base, the sectional view of which along line XV-XVof FIG. 15E is similar to that of the base 1910 illustrated in FIG. 16.

This base can make it possible to detect the hole 83 in which theprotuberance 702 a is connected. This may for example be obtained byelectronic impedance measuring means.

This is advantageous in particular for safety reasons. Controlelectronics can then act such that the electrical power is oriented onlytoward the hole 83 in which the protuberance 702 a is connected, and notin the other holes of the base 1915.

FIG. 17A and FIG. 17B (sectional view along line XVII-XVII of FIG. 17A)show a sixth alternative embodiment of the base illustrated in FIG. 5.

Unlike the upper layer 81 of the base 80, the upper layer 1921 of thebase 1920 is not a continuous layer. The flexibility of the upper layeris therefore improved.

In the case of the example illustrated in FIG. 17, the upper layer 1921is formed by a plurality of rings not mechanically connected, but othershapes and structures can be considered (for example, a plurality ofrings connected to one another by strips).

FIG. 17B also shows the plug 700 once connected to the base 1920.

In an alternative embodiment not illustrated in the figures, theprotuberances of the plugs perform an elastic function. They may thus bespring-mounted (“pogo pins”) or mounted on an elastomer material actingas a spring. Alternatively, the protuberances of the plugs can be madeentirely from an electrically conductive elastomeric material, forexample an elastomeric material filled with metal elements. This mayallow a better electrical contact to be established.

FIGS. 18 and 19 diagrammatically show how the electrical connectoraccording to the invention can be used in electrostimulation devices:

-   -   a self-adhesive cutaneous electrode 1900, which comprises a base        1901 according to the third embodiment of the invention (FIG.        5B),    -   a patch 2000 generating impulses, which comprises a base 2001        according to the fifth alternative embodiment (FIG. 16).

Electrical connectors according to other embodiments of the inventioncan also be used in such electrostimulation devices.

FIG. 18 shows that the cutaneous electrode 1900 comprises anelectrically conductive substrate 1902, for example a polymer filledwith carbon black or metallic elements, or a conductive textilematerial, and hydrogel layers 1903, intended to establish electricalcontact with the user's skin.

The cutaneous electrode 1900 comprises, on its upper face, a base 1901according to the third embodiment of the invention. The base 1901 makesit possible to connect the cutaneous electrode 1900 to an electricalwire comprising a plug.

FIG. 19A shows that the patch 2000 comprises a main part 2002 that inparticular contains electronic components and a power source.

It comprises, on its lower face, layers of hydrogel 2003, intended toestablish electrical contact with the user's skin, and, on its upperface, a base 2001 according to the fifth alternative of the invention.

The base 2001 makes it possible to connect the patch 2000 to anelectrical wire comprising a plug.

It may also act as an upper encapsulating layer for the patch 2000.

The base 2001 comprises an upper layer 2004 playing a magnetic role, anintermediate layer 2007 playing a mechanical role, and a lower layer2005 playing an electrical role.

The lower layer 2005 is made up of two parts 2005A and 2005B, which areseparate and not electrically connected. Holes 2006 emerge on zonescomprising both a portion of the part 2005A and a portion of the part2005B.

FIG. 19B is an electrical diagram of the patch 2000.

The part 2005A is connected to the negative pole of a power source 2008.The part 2005B is connected to the ground (GND) of the electroniccircuits 2009 and 2010. The positive pole of the power source 2008 isconnected to the power supplies (V_(BAT)) of the electronic circuits2009 and 2010. The output (V_(STIM)) of the electronic circuit 2010 isconnected to the hydrogel layers 2003.

The electronic circuit 2010 serves to generate electrostimulationpulses.

The electronic circuit 2009 may have several roles, in particular:

-   -   warning the user when the patch 2000 is turned on, for example        through a visual or audio signal,    -   a communicating with the user, for example by radio waves, i.e.,        sending information to the user or receiving information from        the user,    -   steering the electronic circuit 2010, i.e., ordering the start        or stop of a certain electrostimulation program, characterized        in particular by the amplitude, frequency and duration of the        pulses.

During the use of the patch 2000, two cases may arise:

-   -   1) No plug is connected to the base 2001 of the patch 2000.        -   In this case, the switch formed by the two parts 2005A and            2005B is in an open state. Indeed, the two parts 2005A and            2005B are not electrically connected. The electronic            circuits 2009 and 2010 are therefore not powered by the            power source 2008. In other words, the patch 2000 is turned            off and does not consume energy.    -   2) A plug is connected to the base 2001 of the patch 2000.        -   In this case, the switch formed by the two parts 2005A and            2005B is in a closed state. Indeed, the protuberance of the            plug, which is inserted in a hole 2006, allows the            electrical connection of the part 2005A to the part 2005B.            The electronic circuits 2009 and 2010 are therefore powered            by the power source 2008. In other words, the patch 2000 is            powered on and consumes energy coming from the source 2008.

In this case, as mentioned above, the electronic circuit 2009 can:

-   -   warn the user that the patch 2000 is powered on,    -   transmit information to the user or be ready to receive        information from the user,    -   steer the electronic circuit 2010.

Thus, in the first case (switch open, patch off), no electrostimulationcurrent circulates in the user's body.

However, in the second case (switch closed, patch powered on), anelectrostimulation current does not necessarily circulate in the user'sbody. Indeed, in order for an electrostimulation current to circulate inthe user's body, it is necessary on the one hand for the electricalelectrostimulation path to be established, as described later, and onthe other hand for the electronic circuit 2009 to authorize theelectronic circuit 2010 to start an electrostimulation program.

The advantage of the base 2001 according to the fifth alternative of theinvention is to perform both a connector and switch function. This makesit possible not to have to integrate a conventional switch into thepatch 2000. This is interesting in particular if one wishes for thepatch 2000 to remain a thin and flexible object.

FIG. 20A shows a user (seen from behind) wearing the self-adhesivecutaneous electrode 1900 and the patch 2000 on the lower back.

The self-adhesive cutaneous electrode 1900 is connected to the user'sskin via the hydrogel layers 1903.

The output (V_(STIM)) of the electronic circuit 2010 of the patch 2000is connected to the user's skin via the hydrogel layers 2003.

FIG. 20A shows that the self-adhesive cutaneous electrode 1900 and patch2000 are interconnected via an elastic band 2100.

This band 2100 is illustrated in top view in FIG. 20B.

It comprises an electrically conductive track 2103, interconnecting twoplugs 2101 and 2102, which are intended to be connected to the bases1901 and 2001.

The track 2103 is for example a metal/polymer bilayer, fastened on theelastic band 2100. The track 2103 can have a serpentine shape, as forexample described in FIG. 3 of the document [R. Carta et al., Design andimplementation of advanced systems in a flexible-stretchable technologyfor biomedical applications, Sensors and Actuators A 156 (2009) 79-87].In this way, the elastic band 2100 can be stretched without risk ofdamaging the track 2103.

The plug 2101 on the elastic band 2100 is connected to the base 1901 ofthe cutaneous electrode 1900. The plug 2102 on the elastic band 2100 isconnected to the base 2001 of the patch 2000.

Thus, the negative pole of the energy source 2008 is connected to theuser's skin via the hydrogel layers 1903. In this way, an electricalelectrostimulation path is established: an electrical current cancirculate in the user's body between the hydrogel layers 2003 (which areat the electrical potential V_(STIM)) and the hydrogel layers 1903(which are at the electrical potential of the negative pole of the powersource 2008).

The advantages of electrical connector according to the invention usedin the cutaneous electrode 1900 and the patch 2000 are as follows:

-   -   the bases 1901 and 2001 can be thin or even flexible, which is        comfortable for the user;    -   the connection between the cutaneous electrode 1900 and the        patch 2000, via the bases 1901 and 2001 and the plugs 2101 and        2102, can be done quickly without exerting pressure on the        user's skin and without visual inspection;    -   the base 1901, 2001, respectively, has a large number of        potential connection zones (the holes of the base), these        connection zones covering a large portion of the upper surface        of the cutaneous electrode 1900 (of the patch 2000,        respectively). Thus, for a given length of elastic band 2100,        the user is offered great freedom over the distance separating        the cutaneous electrode 1900 from the patch 2000. Furthermore,        the user can easily connect the elastic band 2100 such that it        is not to stretched (in which case the risk of accidental        disconnection would be increased, and the elastic band 2100        would be a source of bother since it would compress the user's        body), or too slack (in this case, the elastic band 2100 would        be a source of bother because it would “dangle”).

The elastic band 2100 can comprise a first tongue allowing the user todisconnect the plug 2101 from the base 1901 easily, and a second tongueallowing the user to disconnect the plug 2102 from the base 2001 easily.

Lastly, the elastic band 2100 can be integrated into a piece ofclothing.

FIGS. 21 to 26 illustrate several forms of a connector according to theinvention including a male base and a female plug including a cavity.

The base comprises a stack of layers, advantageously thin or evenflexible, and a plurality of protuberances.

Thus, FIGS. 21 and 22 illustrate a first embodiment of such a connector,in which the base comprises:

-   -   a plurality of protuberances,    -   an intermediate layer having an electrical and magnetic        function, on which the protuberances are made,    -   a lower layer having a mechanical function.

One alternative of this first form consists of the intermediate layerbeing eliminated, the lower layer also performing an electrical functionand a potential magnetic function.

FIGS. 23 and 24 illustrate a second form of such a connector, in whichthe base comprises:

-   -   a plurality of protuberances having an electrical and magnetic        function,    -   a lower layer having a mechanical function, on which the        protuberances are formed.

FIGS. 25 and 26 illustrate a third embodiment of such a connector, inwhich the base comprises:

-   -   a plurality of protuberances having a magnetic function,    -   an intermediate layer having an electrical function, on which        the protuberances are formed,    -   a lower layer having a mechanical function.

One alternative of this third form (not illustrated in the figures)consists of the protuberances performing an electrical function and theintermediate layer performing a magnetic function.

In each of these forms:

-   -   The base comprises either protuberances having an electrical        function, or a layer having an electrical function. The elements        of the base having an electrical function (protuberance or        layer) are intended to establish electrical contact with the        part of the plug having an electrical function.    -   The elements of the base having an electrical function are        formed from an electrically conductive material.    -   If the base comprises a layer having an electrical function,        this layer is preferably thin, or even flexible.    -   The base comprises either protuberances having a magnetic        function, or a layer having a magnetic function. The elements of        the base having a magnetic function (protuberance or layer) and        the part of the plug having a magnetic function are intended to        exert an attractive magnetic force on one another.    -   The elements of the base having a magnetic function are formed        from a ferromagnetic material or a magnetized material.    -   If the base comprises a layer having a magnetic function, this        layer is preferably thin, or even flexible.    -   The layer of the base having a mechanical function serves as a        support for a plurality of protuberances. It is preferably thin,        or even flexible.    -   Any one of the protuberances is intended to be inserted in the        cavity of the plug and to thereby prevent accidental        disconnection due to lateral forces, i.e., forces in the plane        of the base.    -   The height of the protuberances is great enough for them to        perform their lateral maintaining function of the plug.        Advantageously, the height of the protuberances is comprised        between 0.1 mm and 5 mm, preferably between 0.5 mm and 2 mm.    -   The surface density of protuberances on the base is high enough        to allow a quick connection with no visual inspection.    -   This is facilitated by the action of the magnetic forces.        However, this density of protuberances makes it possible to        obtain a connection with no visual inspection, even in the        absence of parts performing a magnetic function inside the        connector. However, in the presence of parts performing a        magnetic function, one can see that a small lateral movement of        the plug near the surface of the base suffices for the magnetic        forces to begin their action and assemble the two parts of the        connector, causing the insertion of one of the protuberances of        the base into the cavity of the plug.    -   In other words, the high surface density of potential connection        zones (the protuberances of the base), combined with the action        of the magnetic forces, facilitates a quick connection with no        visual inspection.    -   Advantageously, the diameter of the protuberances (considering        cylindrical protuberances) is comprised between 0.1 mm and 10        mm, preferably between 0.5 mm and 5 mm.    -   Advantageously, the center-to-center distance between two        adjacent protuberances is comprised between 1.5 times the        diameter and 10 times the diameter, preferably between 1.5 times        the diameter and 5 times the diameter.    -   Advantageously, the protuberances of the base are distributed        uniformly over the surface of the base.    -   If the base is intended for a device worn in the form of a        patch, the sum of the surfaces occupied by the protuberances        advantageously corresponds to more than 1% of the total surface        of the patch, and preferably more than 5% of the total surface        of the patch.    -   Furthermore, in all of these forms, the plug comprises:    -   a cavity,    -   a part having an electrical function (i.e., a part made from an        electrically conductive material),    -   a part having a magnetic function (i.e., a part made from a        ferromagnetic material or a magnetized material).    -   A same part in the plug can perform both an electrical and        magnetic function.

In reference first to FIGS. 21 and 22, FIGS. 21A (top view) and 21B(sectional view along line XXI-XXI in FIG. 21A) show the base 2300 ofthe electrical connector.

The base 2300 comprises a plurality of protuberances 2301 (here forminga periodic network), an intermediate layer 2302 having an electrical andmagnetic function, and a lower layer 2303 having a mechanical function.

The protuberances 2301 are for example made from metal. The intermediatelayer 2302 is for example a flexible sheet of magnetic stainless steel.The lower layer 2303 is for example a flexible layer of polymer or atextile material.

FIGS. 22A (top view) and 22B (sectional view along line XXII-XXII inFIG. 22A) show the plug 2200 of the electrical connector.

The plug 2200 comprises a cylindrical part 2201 having an electrical andmagnetic function defining a cavity 2203 that is closed by a cylindricalpart 2202 forming the base of the plug.

The two cylindrical part 2201 and 2202 are centered around a same axis.

The part 2201 is for example a part made from aluminum-nickel-cobalt, orsamarium-cobalt, or neodyme-iron-boron, which are magnetizedelectrically conductive materials. The part 2202 is for example a metalpart.

FIG. 21B also shows the plug 2200 once connected to the base 2300.

One of the protuberances 2301 is inserted into the cavity 2203, whichprevents accidental disconnection due to lateral forces, i.e., forces inthe plane of the base 2300.

The intermediate layer 2302 establishes electrical contact with the part2201. The intermediate layer 2302 and the part 2201 exert an attractivemagnetic force on one another.

In reference now to FIGS. 23 and 24, FIGS. 23A (top view) and 23B(sectional view along line XXIII-XXIII in FIG. 23A) show the base 26 ofthe electrical connector.

The base 2600 comprises a plurality of protuberances 2601 (here forminga periodic network) having an electrical and magnetic function, and alower layer 2602 having a mechanical function.

The protuberances 2601 are for example made from magnetic stainlesssteel. The lower layer 2602 is for example a flexible layer of polymeror textile material.

FIGS. 24A (top view) and 24B (sectional view along line XXIV-XXIV inFIG. 24A) show the plug 2500 of the electrical connector.

The plug 2500 comprises a cylindrical part 2501 and a cylindrical part2502 forming the base of the plug and having an electrical and magneticfunction.

The part 2502 forms, with the part 2501, a cavity 2503. The twocylindrical part 2501 and 2502 are centered around a same axis.

The part 2501 is for example a part made from metal. The part 2502 isfor example a part made from aluminum-nickel-cobalt, or samarium-cobalt,or neodyme-iron-boron, which are magnetized electrically conductivematerials.

FIG. 23B also shows the plug 2500 once connected to the base 2600.

One of the protuberances 2601 is inserted into the cavity 2503, whichprevents accidental disconnection due to lateral forces, i.e., forces inthe plane of the base 2600.

The protuberance 2601 establishes electrical contact with the part 2502.The protuberance 2601 and the part 2502 exert an attractive magneticforce on one another.

In reference lastly to FIGS. 25 and 26, FIGS. 25A (top view) and 25B(sectional view along line XXV-XXV in FIG. 25A) show the base 2900 ofthe electrical connector.

The base 2900 comprises a plurality of protuberances 2901 (here forminga periodic network) having a magnetic function, an intermediate layer2902 having an electrical function, and a lower layer 2903 having amechanical function.

The protuberances 2901 are for example made from magnetic stainlesssteel. The intermediate layer 2902 is for example a flexible coppersheet. The lower layer 2903 is for example a flexible layer made from apolymer or textile material.

FIGS. 26A (top view) and 26B (sectional view along line XXVI-XXVI inFIG. 26A) show the plug 2800 of the electrical connector.

The plug 2800 comprises a cylindrical part 2801 having an electricalfunction, and another cylindrical part 2802 forming the base of the plugand having a magnetic function. The part 2802 forms, with the part 2801,a cavity 2803. The two cylindrical parts 2801 and 2802 are centeredaround a same axis.

The part 2801 is for example a metal part. The part 2802 is for examplea part made from ferrite, or aluminum-nickel-cobalt, or samarium-cobalt,or neodyme-iron-boron, which are magnetized materials.

FIG. 25B also shows the plug 2800 once connected to the base 2900. Oneof the protuberances 2901 is inserted into the cavity 2803, whichprevents accidental disconnection due to lateral forces, i.e., forces inthe plane of the base 2900. The intermediate layer 2902 establisheselectrical contact with the part 2801. The protuberance 2901 and thepart 2802 exert an attractive magnetic force on one another.

Throughout the preceding description, the connector according to theinvention includes a plug. However, the invention is not limited to thisembodiment. The connector could include several plugs intended to beconnected in the same base. The number of plugs will, however, bestrictly lower than the number of connecting means provided in the base.

The reference signs inserted after the technical features appearing inthe claims are intended solely to facilitate the understanding of thelatter and cannot limit the scope thereof.

The invention claimed is:
 1. An electrical connector for a deviceconfigured to be fixed on the skin of a user, comprising: a base securedto the device; and a plug configured to be secured to an electricalconductor, wherein the plug comprises a first connection means and thebase comprises a plurality of second connection means, each of theplurality of second connection means being individually configured forcooperating with the first connection means of the plug to ensure aconnection between the base and the plug, the plug and the baseincluding magnetic means on the plug and corresponding magnetic means onthe base, the plurality of second connection means of the base includinga plurality of holes and the first connection means of the plugincluding a protuberance, the magnetic means exerting attractivemagnetic forces causing an insertion of the protuberance of the plug inone of the holes of the base.
 2. The connector of claim 1, wherein acenter-to-center distance between adjacent second connection meansincluded in the plurality of second connection means of the base isbetween 1.5 and 10 times a diameter of one of the plurality of secondconnection means.
 3. The connector of claim 1, wherein the plurality ofsecond connection means of the base are distributed uniformly over asurface of the base.
 4. The connector of Claim 1, wherein the plugcomprises an annular part protruding on the base and extending aroundthe protuberance, the base comprising, around each hole, an annularopening to receive the protruding annular part of the plug.
 5. Theconnector of Claim 1, wherein the plug includes the protuberance havinga flared shape becoming narrower as it moves away from the base, theholes of the base including a corresponding shape to receive theprotuberance.
 6. The connector of Claim 1, wherein the protuberance ofthe plug has a flared shape becoming wider as it moves away from thebase, the holes of the base having a corresponding shape to receive theprotuberance.
 7. The connector of Claim 1, wherein the protuberance ofthe plug performs an elastic function.
 8. The connector of claim 1,which includes a plurality of plugs, the number of which is smaller thanthat of the plurality of second connection means of the base.
 9. Amedical device intended to be fixed on the skin of a user, comprising anelectrical connector of claim
 1. 10. The device of claim 9, wherein theplurality of second connection means of the base are advantageouslydistributed so as to occupy more than 1% of the total surface area ofthe device.
 11. The connector of claim 1, wherein the base is made up ofa stack of at least two layers, one of the at least two layersperforming at least a mechanical support function, wherein the at leasttwo layers also performing an electrical function and optionally amagnetic function, wherein the plurality of holes of the base traversingat least the one of the at least two layers acting as mechanicalsupport, and wherein the plug comprises a base and the protuberanceperforming the electrical function and optionally the magnetic function.12. The connector of claim 11, wherein the layer of the base performingan electrical function is made up of two separate parts that are notelectrically connected, the protuberance or the base of the plug makingit possible to electrically connect these two parts when the plug isconnected to the base.
 13. The connector of claim 11, wherein the stackmaking up the base comprises a first layer performing the mechanicalsupport function and a second layer performing the electrical functionand optionally the magnetic function, wherein the plurality of holes aretraversing the stack, and wherein the electrical function and optionallythe magnetic function of the plug is performed by the base of the plug.14. The connector of claim 13, wherein a layer traversed by the holes isa discontinuous layer.
 15. The connector of claim 11, wherein the stackmaking up the base successively comprises a first layer performing theelectrical function, a second layer performing the mechanical supportfunction and optionally a third layer performing the magnetic function,the holes traversing the third layer performing the magnetic function,wherein the third layer cooperates with any magnetic function of theplug being performed by the base and the electrical function of the plugbeing performed by the protuberance.
 16. The connector of claim 15,wherein the second layer performing the mechanical support function alsoperforms the magnetic function.
 17. The connector of claim 11, whereinthe stack making up the base comprises a first layer performing theelectrical function and a second layer performing the mechanical supportfunction, the first layer performing the electrical function also beingable to perform the magnetic function, the holes only traversing thesecond layer performing the mechanical support function, the electricalfunction and optionally the magnetic function of the plug beingperformed by the protuberance.
 18. The connector of claim 17, whereinthe protuberance of the plug comprises two parts performing theelectrical function and optionally the magnetic function, separated byan insulator, the layer of the base that performs the electricalfunction being designed to transmit electrical signals.
 19. Theconnector of claim 17, wherein the layer of the base that is nottraversed by the holes is a discontinuous layer, having a form of a gridor independent parts that are not electrically connected.